The Portugal international has hit out at the referee in the wake of los Blancos' Clasico loss, and he feels the official favoured Barca during the controversial contest
Madrid were awarded a controversial spot kick shortly after half-time, but Mallenco also pointed to the spot in Barcelona's favour twice in the remainder of the game - while also dismissing Sergio Ramos - and Ronaldo feels the official deliberately favoured the Catalans.
"Undiano Mallenco is not suitable for games like this. We were playing against 12. It's always the same. It's like they don't want us to win and wanted Barcelona back in the title race," Ronaldo told reporters
"I am not looking for excuses, but I don't want to stay quiet on this. The referee was not at the required level for a big game like this.
"I have been here for five years now and I know how things work. If Barcelona had lost, they would have been out of the title race. I have never seen Real Madrid being favoured by the referees."
Ronaldo remains confident that Madrid will win the Liga title, however, irrespective of Sunday's defeat at the Bernabeu.
"Regardless of all that happened, Madrid will still win La Liga."
Carlo Ancelotti's side currently sit joint first with Atletico Madrid, while Barca are third, just a single point behind.